This is a cut and paste from Facebook. I don’t think I’m violating copyrights. He’s saying, genetically, we’re going downhill. The counter argument is better nutrition and generally safer environments are countering the effects. But, look at what the authoritarians do, they cut education funding, they don’t feed the poor, they care about housing.
So, where is this heading?
Stanford geneticist Gerald Crabtree published research in Trends in Genetics arguing that human intelligence may have started slowly declining ever since societies moved away from hunter-gatherer lifestyles.
The argument is specific and worth understanding carefully before dismissing.
Of the roughly 5,000 genes Crabtree identified as the basis for human intelligence, accumulated mutations over generations have gradually degraded the integrity of that genetic foundation. He concluded that humans may have reached their intellectual peak somewhere between 2,000 and 6,000 years ago.
The core mechanism he identified is that unlike many biological systems with built-in redundancy and fail-safes, intelligence genes operate more like links in a chain. A mutation in any single link can compromise the entire system, making the genetic architecture of intelligence surprisingly fragile compared to other biological functions.
Crabtree himself acknowledged that any genetically based decay in intelligence would be extremely slow, operating across thousands of years, not generations.
The scientific community did not receive this warmly. Geneticist Steve Jones at University College London called the papers “arts faculty science,” saying the hypothesis lacked sufficient supporting data.
There is also a counter-argument built into the data that Crabtree himself acknowledged. Average IQ scores globally rose steadily throughout the 20th century, a phenomenon called the Flynn Effect. Better nutrition, education, and cognitive stimulation appear to have more than compensated for any slow genetic drift.
The tension between those two trends, genetic fragility versus environmental enrichment, is the actual scientific debate. Neither side has closed it.